<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

</body>
<script>
    if (navigator.userAgent.match("Windows"))
    {
        alert("Windows")
    }
    else if(navigator.userAgent.match("Android"))
    {
        alert("安卓")
    }

</script>
</html>